The present invention relates generally to a pressure sensor device to be incorporated into a car control device of an electropneumatic brake for use in a train and more specifically, to improvements in the pressure sensor module.
In general, a train is comprised of a consist of one or more locomotives followed by a series of cars, and a pneumatic brake pipe extending through the train for the pneumatic brake. In recent years, each of the train cars and each of the locomotives have been serially connected by a power and communication trainline. Additionally, each car has an electropneumatic brake system. The serial electric power network and the pneumatic brake network have been integrated to form an electropneumatic braking system which is in communication with the power and communication trainline, which not only delivers power to each of the cars but also provides a communication link, enabling identification and serialization of a train.
In order to integrate the pneumatic and electrical systems in a network, the prior art devised a car control device for placement in each car, and the car control device was then placed in contact with an ID module and the power and communication trainline. An example of a system is shown in U.S. Pat. No. 5,967,465 to Lumbis et al and a car control device is disclosed in U.S. Pat. No. 5,967,620 to Truglio et. al.
A car control device necessarily involves the linking and intertwining of several systems. The car control device is comprised of a pressure sensing system, a control valve system, a power management system, a functional control system, and a manifold. The control valve system is comprised of a plurality of valves which may be electrically controlled in response to electrical signals received from the functional control module to pneumatically control the pneumatic brakes. A plurality of pressure transducers comprising a pressure sensor module communicates with the functional control system. Therefore, a car control device involves an intricate network of systems in fluid and/or electrical communication with one another.
A pressure sensor module (PSM) is an integral part of a car control device. The PSM must be in fluid communication with the manifold in order to detect and determine the pressure at various points in a manifold within the car control device, and the PSM must also be in electrical communication with the functional control module, which provides braking and communication signals, based on information received from the PSM, to the network. Preferably, the pressure sensor module is mounted inside the housing adjacent to the control valve module and the power management module.
The pressure sensor module comprises a casing and a plurality of pneumatic input ports integrally configured on a first face of the casing and to be in fluid communication with the manifold. The ports are configured so that mounting of the module of the pressure sensor module to the manifold sealably connects each of the pneumatic input ports to an aperture in fluid communication with the manifold. Preferably, the casing is sealed except for the ports. A plurality of transducers are inside the casing and in communication with its own port. Each of the transducers is electrically connected to the functional control module.
The pneumatic input ports of the pressure sensor module are connected respectively to receive fluid communication from ports on the manifold which correspond to an emergency reservoir, a brake pipe, a brake cylinder, control valve, and the external atmosphere. The pressure sensed at each of the emergency reservoir, brake pipe, brake cylinder and control valve pressure ports is compared to the atmospheric reference, then translated into a voltage by the respective pressure transducers, thereby producing a signal from the transducers that is proportional to a gauge pressure for each of the respective ports. The casing comprises at least one bore for receipt of a fastener which attaches the casing to the manifold.
The pressure sensor module has a multi-pin electrical receptacle on a second face of the casing. The receptacle is configured such that each of the transducers has an output electrically connected to a respective pin. Additionally, a pair of pins of the receptacle correspond to a pair of common voltage inputs to each of the transducers. A cable is mated with the receptacle in order to transmit these signals to the functional control module of the car control device and provide voltage to the pressure sensor module.
The pressure sensor module further comprises an ambient input port in fluid communication with the external atmosphere. The ambient input port is connected to a conduit that extends through the housing to provide direct fluid communication with atmospheric pressure.